Doffer comb mechanism



Jan. 9, 1968 HALE L 3,362,048

DOFFER CQMBMECHANISM Filed March 16, 1965 1 6 Sheets-Sheet 1 O INVENTOR29 25 36 ARTHUR NHALE'x ROBERT ESMITH Jan. 9, 1968 A. N. HALE ETALDOFFER COMB MECHANISM 6 Sheets-Sheet 2 Filed March 16, 1965 'INVENTORSARTHUR NHALEQ ROBERT E SMlTH M ATTORNEYS Jan. 9, 1968 A. N. HALE ETAL3,362,048 I DOFFER COMB MECHANISM I Filed March 16, 1965- e Sheets-Sheet5 d, HQ] H H JJ 4 I;\'\E.\.T IRS ARTHUR MHALE a IQOBERT E.'SM\TH Jan. 9,1968 Y A. N. HALE ETAL 3,362,048

' DOFFER COMB MECHANISM Filed Mrch 16, 1965 s Sheets-Sheet 4 0 x N IINVENTORj m m ARTHUR NHALEQ- ROBERT ESMITH Jan. 9, 1968 A. N. HALE ETALDOFFER. COMB MECHANISM mm s 2 m mam ow m H 6 VET Filed March 16, 1965United States Patent 3,362,048 DOFFER COMB MECHANISM Arthur N. Hale,Park Ridge, and Robert, E. Smith, Chicago, 11]., assignors to UnionSpecial Machine Company, Chicago, 111., a corporation of Illinois FiledMar. 16, 1965, Ser. No. 440,150 25 Claims. (Cl. 19-106) ABSTRACT OF TIEDISCLOSURE A doffer comb mechanism is provided utilizing a rotary shaftand an oscillatory shaft, with a comb blade attached to the oscillatoryshaft at a fixed distance therefrom. The oscillatory shaft is drivenfrom both ends of the rotary shaft, and the comb blade is carried byarms extending from the oscillatory shaft, the arms being disposed atnode points of the fundamental resonance of the comb blade, to eliminateunwanted vibrations. Other means comprising wires facilitate properpositioning of the blade from the oscillatory shaft are provided alongits length.

The following specification relates to a novel improvement in doifercomb mechanism adapted for removing stock from the dofier cylinder of acarding machine.

In present day practice, the output efficiency of a carding machine forcotton and similar fibers depends on the speed at which the doifer combcan be oscillated. The maximum speed at which the current dolfer comboscillating mechanism operates, is approximately 1800 cycles per minute.This constitutes an economic limitation on fiber processing.

It is therefore an object of this invention to provide a new andimproved doffer comb mechanism capable of operating successfully athigher speed in excess of 1800 cycles per minute.

A further object of the invention is to avoid excessive wear on thesupporting bearings or eccentric mechanism at the increased speed.

Among the objects of the invention is to insure an even stroke of thecomb.

A further object of the invention is to effect successful operation ofthe machine without developing disturbing resonance.

A still further object of the invention is to control the horizontaldeflection of the comb toward and from the dofiing cylinder.

As illustrating this invention, the preferred form thereof has beenshown by way of example on the accompanying drawings in which:

FIGURE 1 is the side elevation of the output end of a carding machineWith which the novel combination is associated;

FIGURE 2 is a plan view of the same;

FIGURE 3 is a side elevation of the same;

FIGURE 4 is a front elevation partly in section of the right end of themounting on the line 4-4 on FIGURE 3;

FIGURE 5 is a partial plan View, parts broken away, of the right end asshown in FIGURE 3;

FGIURE 6 is a partial front elevation of the left end thereof;

FIGURE 7 is a partial plan view partly in horizontal section on the line7-7 in FIGURE 6;

FIGURE 8 is a side view of a flange of the tubular portion of theoscillating shaft;

FIGURE 9 is a vertical section of the outer connecting bracket for theend support of the oscillating shaft;

FIGURE 10 is a side elevation of the same;

FIGURE 11 is a plan view of the left-hand end support for theoscillating shaft;

3,362,048 Patented Jan. 9, 1968 FIGURE 12 is a vertical section on theline 1212 on FIGURE 5;

FIGURE 13 is a vertical section on the line 13-13 on FIGURE 5;

FIGURE 14 is a fragmentary elevation of the doffer comb as seen fromline 14-14 on FIGURE 5;

FIGURE 15 is a transverse vertical section on the lin 1515 of FIGURE 7;

FIGURE 16 is a perspective view of a reinforcing bracket shown in FIGURE15;

FIGURE 17 is a transverse cross-section on the line 17-17 of FIGURE 13,and

FIGURE 18 is a plan view of one of the separate end support shafts ofthe rotary drive shaft.

FIGURE 19 is a fragmentary elevational view showing the countersinksflanking one of the Wire exit holes in the oscillating shaft tube.

In brief, the invention includes, among other features which will bediscussed later, a dual drive unit for oscillaitng the doifer comboscillating shaft. This dual drive unit comprises an eccentric mechanismon either side of the oscillating shaft. Both eccentric mechanisms areconnected with each' other by a rotary drive shaft which extends aboveand parallel to the oscillating shaft. Like the oscillating shaft, therotary drive shaft is supported by two upright structures and is drivenby a belt which is trained over a ratio multiplier pulley mounted on athird shaft disposed in the base portion of one of the uprightstructures. The oscillating shaft supports a lightweight comb blade bymeans of two supporting arms. A plurality of steel wires are strung fromthe comb blade to the oscillating shaft, each individual wire passingthrough a spacer tubing interposed between the comb and the oscillatingshaft.

In developing this new unit it has been found that, when operating adoffer oscillating mechanism at high speeds, say above 1800 rpm, anumber of problems arise, some of which are (a) the torsional stress inthe oscillating and drive shafts, (b) the deflection imposed upon theoscillating shaft by the inertia forces of its own mass and the mass ofthe comb blade, (c) the deflection of the comb blade in relation to thedoffer cylinder, (d) the resonant vibration in the oscillating shaft,the drive shaft and the comb blade, and (e) the total effect of allthese factors upon the driving mechanism and the stroke of the comb. Theproblems arising through torsion are some of the factors that cut downthe effectiveness of conventional doffer comb mechanisms. This becomesapparent especially with respect to the speed and performance of thecomb. These torsion problems are mainly caused by the fact that inconventional doffer mechanisms the drive is imparted to the oscillatoryshaft from just one side. Torsional stress will cause the oscillatoryshaft to twist and its bearings to wear out more rapidly. Consequently,the comb will no longer assume parallelism with the oscillatory shaftduring operation so that the stroke becomes uneven, resulting in alesser quality of the sliver. We have obviated this torsion problem bysupplying an identical driving force at both ends of the oscillatoryshaft. For this purpose, we have provided dual drive meansinterconnected by a drive shaft extending in parallelism with theoscillatory shaft.

A further step toward this end was to decrease the load imposed upon theoscillatory shaft and its bearings by reducing the weight of the combblade and the supporting arms as much as possible. We also mountedcounterweights on the ends of the drive shaft for balancing thereciprocating motion of the connecting rods driving the oscillatoryshaft.

In order to prevent damages caused by excessive vibration, especially byresonant vibration, efforts were made to raise the resonant frequency ofthe important components involved so far that resonance could not beattained during operation of the mechanism. As a rule, the resonantfrequency is proportional to the square root of the ratio of thestiffness of the system to its mass. In accordance with this rule, weraised the resonant frequency of the drive and the oscillating shaft to8000 cycles per minute by giving them a relatively high stiffness incomparison to their weight. This was accomplished by constructing eachshaft with a central tubular portion.

On the other hand, there was the problem of raising the resonantfrequency of the comb blade high enough so that it could not be excitedduring the operation of the doffer comb mechanism. This goal wasachieved by changing the mode or shape in which the comb can vibrate. Itis known in the art that the resonant frequency of a supported bardepends on the mode or shape which it assumes when vibrating. Thedetermining factor for this mode, however, is mostly the manner of itssupport.

If a bar is supported at its ends and is deflected in the middle (mode)while vibrating, it will resonate at a certain frequency. If the samebar is supported at a certain distance away from its ends and its middleand ends are deflected in opposite directions while vibrating, it willresonate at an even higher frequency. If, finally, said bar is sosupported that its ends and middle will be deflected in the samedirection while vibrating, then the resonant frequency is still higherthan in the foregoing case. We have found we obtain such a mode ofvibration as stated in the latter case by supporting the comb blade atthe node points of its fundamental resonance. The so obtained resonantfrequency of the comb blade is so high that the danger of excitingresonance in the blade is virtually eliminated.

Summarizing the facts outlined above we may say that the resonantfrequency of the doffer comb blade is so high that we could not driveour mechanism fast enough to excite it. Also, we may say that theresonant frequency of the drive shaft and the oscillating comb shaft isapproximately 8000 r.p.m. In the latter case, this means that if We hadto deal with a pure harmonic in the driving motion, we could run ourmechanism at a top speed of somewhat less than 8000 r.p.m., as in thiscase only the force component at 8000 r.p.m. would cause our mechanismto resonate. However, due to the use of connecting rods, there is asecond harmonic in the motion which constitutes a force component thatcould excite resonance in the above-mentioned shafts at 4000 r.p.m.Consequently, this limits our driving speed to somewhat less than 4000r.p.m. Even so, the driving speed of our mechanism is considerablyhigher than that of conventional doffer comb mechanism.

The vertical deflection, since it is very minute, offers no problem whenthe blade is oscillated below the resonant frequency. However, thehorizontal deflection of the blade in the direction of the cylinder isquite another problem and one which must be stringently controlled.

In order to obtain such control, a number of steel wires are strungthrough spacers from the comb blade to the oscillating shaft. Thesespacers serve to keep the blade straight when proper tension is appliedto each wire. It is important that these wires do not function asadditional comb supports and thereby upset the mounting of the comb.Therefore, the wires are at one end pivotalily secured to theoscillating shaft and at the other end secured to the comb blade. Thusthe wire spacer sleeve arrangements may follow every vertical deflectionof the comb blade without causing any resistance there-against. This isof utmost importance, as such resistance could cause a change in themode of the vibrating curve.

In the form illustrated in the drawings, the output end of the cardingmachine is shown with the improved doffer comb mechanism 21 arrangedadjacent the doffer cylinder 22, which has a shaft 23 rotatably mountedin bearings 24, which in turn rest upon the bed 25.

The doffer cylinder has cards 26 armed with teeth 27, which card thecotton or other fiber material so that the filaments are oriented in aparallel web. The oscillating doffer comb, denoted generally by 28,strips the web material for further operation.

The doffer comb 28 is caused to oscillate principally in a verticalplane to and from the surface of the cards 26. This oscillation isprovided by a synchronized dual drive. Two upright frame structures 29are mounted at opposite ends of the bed 25 of the carding machine.

Aflixed to the lower portion of one of said frame structures, dependenton the location of the source of power, is a cast iron housing 30. Anovedrdive shaft 31 is supported by bearings 32 and 33. This shaft has anouter pulley 34.

A belt 35 is trained over pulley 34 and pulley 36 on a drive or powershaft 37. Shaft 37 also drives the shaft 23 of the doffer cylinder.

Referring to FIGURES 4 and 5, a second pulley 38 is connected by meansof a belt 39 to one of two pulleys 40, 41, mounted upon opposite ends ofa rotary shaft 42. By reason of their weights, pulleys 40 and 41 act asflywheel for the rotary shaft 42. This provides a synchronous drive forthe opposite eccentric mechanisms for operating the doffer comb. Inaccomplishing this purpose, there is a separate end support shaft 43, 44journaled in sealed ball bearings 45, 46 in a housing formed in theupper portion of the frames 29, 29.

Pulleys 40 and 41 are mounted on the shafts 43, 44 respectively, thuscoupling the latter to stub portions 47.

Shaft 43 and the stub portion 47 are each provided with aligned keyways48, and receive the key 48. The key is held in position by means such asscrews, and serves as a rigid connection between the end support shafts43, 44 and the intermediate tubular portion. This tubular portioncomprises a steel tube 49. The tube 49 is mounted on inner flanges ofthe stub portions 47, as best shown in FIGURE 4.

The outer portion of each end support shaft 43, 44 is provided with aneccentric 50. This eccentric cooperates with a connecting rod 51, 52.The connecting rods are formed of two members joined together by rivetsor other suitable mean which include bearings 53, 54, 55 and 56. This isa particularly advantageous light weight but sturdy connecting rod,especially easy of manufacture. There is a snap ring '57 which issnapped into a suitable annular groove 58 provided in the eccentricportion 50 of each end support 43, 44, thus holding the connecting rodfirmly in place.

Mounted on the outer end of each of the eccentric portions 50 iscounterweight 59 for balancing the reciprocating motion of theconnecting rods.

The oscillating shaft assembly 60 is mounted below and laterally spacedfrom the rotary drive shaft 42. Like the latter, the oscillating shaftis comprised of a midportion and two end support shafts 61, 62, whichare journaled in a pair of scaled ball bearings 63, 64. The outerportions of both end support shafts terminate in crank arms 65, 66,carrying crank studs 67, 68, to which is linked the lower ends of theconnecting rods 51 and 52. The connecting rods are self-aligning and arelocked in their aligned position by means of a split ring 69, riding onthe beveled outer edge of the crank studs 67, 68. A thrust washer 70,the outside diameter thereof being smaller than the inside diameter ofthe raceway of the bearings 54, 56, contacts the split ring. The thrustwasher 70 is backed by a screw 71 and forces the split ring upon thebevel of the crank stud, wedging it firmly between the latter and theraceway of the bearing 54, 56.

The oscillating shaft 60 is hollow, being made of a steel tube 72. Atits ends, the tube 72 has flanges 73, 74, to which it is attached bysoldering or other suitable means. The mid-portion of the shaft 60 alsocarries the comb 28 and the comb supporting means.

The flanges 73, 74 have a number of circularly oriented slots 75, 76spaced equidistantly from each other and from the center. Each of theseflanges is provided with a pin 77 projecting from its center. These pins77 are adapted to fit into suitable grooves, 78, provided at the innerfaces of the shafts 61, 62. These grooves are continued in the flangeportion of sleeve 80 as illustrated in FIGURE 9 and shown there asnumeral 79. Said sleeve 8!) is fitted over the inner end portions of theshafts 61, 62 and fastened thereto by a key 81 and a set screw 82.

The flange 80 contain an equal number of holes 83 as there are slots '76in the flanges 73, 74-. Said holes 83 are in line with the slots and areadapted to receive mounting bolts 84 with nuts 85. This arrangement is anovel feature of the invention in that by loosening nuts 85, theoscillating shaft can be adjusted in either direction about its centerto the limits of the slots. Further, upon removal of the bolts 84, themid-portion of the oscillating shaft can be disengaged from the rest ofthe mechanism and can be removed without disturbing the set-up of thedoffer comb oscillating mechanism. This means considerable saving inlabor and machine time whenever the removal of the comb blade is calledfor.

The doffer comb 28 is made of light weight material, preferablyhard-coat magnesium and is supported on the oscillating shaft 60 by twoarms 86, 86, preferably spaced on the shaft 60 at points removed fromits ends substantially one-fourth of its length. This conforms to thecase in which oscillation of the ends of the comb 28 are simultaneouswith the vibration of the mid-portion of the shaft. In other words, thecenter and ends of the comb form points of amplitude controlled by theattachment to the arms 86, 86 at the nodes.

The arms 86, 86 are preferably flat, thin steel plates, laminated in twolayers and welded or otherwise joined together. These arms have a numberof perforations which reduce the weight but Without loss of strength. Byusing thin plates for each arm, the ends of the plates may be bent toprovide right angle free ends extending in opposite directions to from aT support, as shown in FIGURE 7. This is in effect a balanced supportfor the comb. The blade of the comb 28 is secured to the arms 86 byscrews, welds or other suitable means.

Suitably spaced along the length of the hollow, oscillating shaft arepairs of aligned openings 87, 88. The aperture 87 is fitted loosely witha bolt 89. This bolt is adjust-ably screw-threaded through a fibre locknut 90. The head of the bolt 8- has a counterbore 91. This counterboreholds a steel 'ball 92 free to adjust itself rotatably.

A steel wire 93 is anchored to the ball 92 and extends through thetubular shaft 60 and for a considerable distance on the far side whereit passes through the comb 28 and is anchored to the latter, as shown inFIGUR ES 13 and 14.

Each wire extends through a spacer sleeve 96 interposed between theoscillating shaft 60 and the comb blade 28. A steel plug 94 is tightlyreceived in the end of the spacer sleeve, adjacent the comb blade. Plug94 is provided with a suitable passage pole for the wire 93 and servesto maintain alignment of the sleeve 96 with the wire 93. The oppositeend of the spacer sleeve is wedgeshaped and the resulting angular endfits within a pair of small countersinks 88' horizontally flanking theWire exit hole 88 of the oscillating shaft, as shown in FIG- URE 19. Thewire 93 is covered with a vibration dampening coating 95 over thedistance between the bolt 89 and the plug 94. By partly unscrewing thebolt 89, tension is applied to the steel Wire 93, thus placing thespacing sleeve 96 under compression. It therefore holds the comb 28definitely spaced, but free to oscillate slightly in a verticaldirection.

In orderto maintain'the comb perpendicular and at right angles to thesleeves 96, some sleeves carry a fixed bracket 97. Each bracket has asemicircular center portion with opposite wings 98, 98. Attachment ofthe brackets to the sleeves provides a rigid alignment of the parts.

The shaft 60 with the comb 28 and its support is unbalanced. In order toadequately counterbalance the shaft in motion, two counterweights 99, 99are adjustably mounted on studs 100, 100, extending radially from theshaft and in a direction opposite to that of the comb 28.

By the arrangement described above, it is possible to accomplish thecomplicated objects of the invention in a novel and improved manner. -Inbrief, it will be apparent that the mechanism avoids excessive wear dueto increased speed. Further, the increased speed is effected withoutdeveloping disturbing resonance.

In addition, the ability to replace the comb blade has been facilitated;the upper or drive shaft may be driven from either end at will, andsuitable adjustable pulleys may multiply the ratio.

The preferred form of the invention having been described by way ofexample solely, it will be evident that minor changes in structure,proportion and material can be made within the scope of the appendedclaims.

What we claim is:

1. A doffer comb mechanism comprising a drive shaft, drive meanstherefor, a cam on each end of the drive shaft, a parallel comb shaft,parallel crank arms one on each end portion of the comb shaft, aconnecting rod connecting each arm with one of said cams, said combshaft having a central tubular portion, means for removably andadjustably attaching said central portion to the end portions, spacedarms on the central portion of the comb shaft, diametrically spaced fromthe crank arms, a comb blade mounted on the arms, a series of hollowspacers at uniformly spaced points on the comb blade and pivotally heldon the near side of the comb shaft, wires from the comb blade runningfreely through the spacers and central portion of the comb shaft andmeans on the opposite side of the said portion for anchoring the wiresunder tension.

2. A mechanism as defined in claim 1 in which the drive shaft has acounterweight at each end opposite the cam.

3. In a doifer comb mechanism for carding machines, an oscillatory shaft, a comb blade attached to said shaft by attachment means andarranged in spaced relation thereto; said attachment means being spacedaxially of the shaft ends, means for supplying driving force withidentical motion to said shaft at both ends thereof, two

arms extending transversely from said shaft, said arms alone carryingthe comb blade at the node points of the fundamental resonance of theblade.

4. In a doffer comb mechanism for carding machines, an oscillatoryshaft, a comb blade attached to said shaft and arranged in spacedrelation thereto, driving means at both ends of said shaft, two armsextending transversely from said shaft, said arms defining means forsupporting the comb blade only at the node points of the fundamentalresonance of the comb blade, spacer means arranged between the combblade and the oscillatory shaft, and means cooperating with said spacermeans for keeping the comb blade, throughout its length, at a fixeddistance from said oscillatory shaft.

5. In Ia doffer comb mechanism for carding machines, an oscillatoryshaft, a comb blade attached to said oscillatory shaft by attachmentmeans and arranged in spaced relation thereto; said attachment meansbeing spaced axially of the shaft ends, and drive means for supplying anidentical driving force to both ends of said oscillatory shaft, saiddrive means comprising a single rotary shaft parallel to andsubstantially the same length as the oscillatory shaft, eccentrics onboth ends of said rotary shaft, parallel crank arms on both ends of saidoscillatory shaft, and connecting rods connecting each of said crankarms With one of said eccentrics.

6. A doifer comb mechanism according to claim 5, wherein said rotaryshaft and said oscillatory shaft are journaled in bearings disposed inspaced support members mounted on the carding machine.

7. A doffer comb mechanism according to claim 5, including spacer meansarranged between said oscillatory shaft and the comb blade and meanscooperating with said spacer means for keeping the comb blade at allpoints of its length at a fixed distance from said oscillatory shaft.

8. A dotfer comb mechanism according to claim 5, wherein the rotaryshaft has a counterweight at each end.

9. In a doifer comb mechanism for carding machines, an oscillatoryshaft, a comb blade attached to said shlaft and arranged in spacedrelation thereto, and means for supplying drive force with identicalmotion to said shaft on both ends thereof; wherein the oscillatory shaftis formed with a central tubular portion and means for removably andadjustably attaching said central portion to the end portions, wherebyadjustments of the position of the central tubular portion may be maderelative to said end portions, or removal and replacement of saidcentral tubular portion can be effected without disturbing thepositioning of said end portions.

10. In a doffer comb mechanism for carding machines, an oscillatoryshaft, a comb blade attached to said shaft and arranged in spacedrelation therto, driving means at both ends of said shaft, two armsextending transversely from said shaft, said arms carrying the combblade at substantially the node points of the fundamental resonance ofthe comb blade, spacer means arranged between the comb blade and theoscillatory shaft, and means cooperating with said spacer means forkeeping the comb blade, throughout its length, at a fixed distance fromthe oscillatory shaft; wherein said spacer means are sleeves, and themeans cooperating therewith for keeping the comb blade at a fixeddistance are wires strung from the oscillatory shaft to the comb blade,said wires being pivotally anchored to the oscillatory shaft at one endand fastened to the comb blade at the other end and carrying said spacersleeves.

11. A doifer comb mechanism according to claim 10, wherein the wires arepivotally anchored by means comprising a hollow bolt holding the end ofthe wire and adjustably tensioning same in the side of said oscillatoryshaft.

12. In a doffer comb mechanism for carding machines, an oscillatoryshaft, a comb blade attached to said shaft and arranged in spacedrelation thereto, driving means at both ends of said shaft, two armsextending transversely from said shaft, said arms carrying the combblade at substantially the node points of the fundamental resonance ofthe comb blade, spacer means arranged between the comb blade and theoscillatory shaft, and means cooperating with said spacer means forkeeping the comb blade, throughout its length, at a fixed distance fromthe oscillatory shaft; wherein said spacer means are pivotally held formovement solely in a plane perpendicular to the axis of the oscillatoryshaft.

13. In a dotfer comb mechanism for carding machines, an oscillatoryshaft, a comb blade attached to said oscillatory shaft and arranged inspaced relation thereto, and drive means at both ends of saidoscillatory shaft, said drive means comprising a rotary shaft,eccentrics on both ends of said rotary shaft, parallel crank arms onboth ends of said oscillatory shaft, and connecting rods connecting eachof said crank arms with one of said eccentrics; wherein said rotaryshaft is formed with a central tubular portion and two end portions, andmeans for removably attaching said central portion to the end portionsfor removal and replacement without disturbing the positioning of saidend portions.

14. In a doffer comb mechanism for carding machines, an oscillatoryshaft, 3. comb blade attached to said oscillatory shaft and arranged inspaced relation thereto, and drive means at both ends of saidoscillatory shaft, said drive means comprising a rotary shaft,eccentrics on both ends of said rotary shaft, parallel crank arms onboth ends of said oscillatory shaft, and connecting rods connecting eachof said crank arms with one of said eccentrics; in which the oscillatoryshaft has a plurality of counterweights diametrically disposed to thearms supporting the comb blade.

15. In a doffer comb mechanism for carding machines, an oscillatoryshaft, a comb blade attached to said oscillatory shaft and arranged inspaced relation thereto, and drive means at both ends of saidoscillatory shaft, said drive means comprising a rotary shaft,eccentrics on both ends of said rotary shaft, parallel crank arms onboth ends of said oscillatory shaft, and connecting rods connecting eachof said crank arms with one of said eccentrics; wherein said rotary shaft carries two flywheels.

16. In a doffer comb mechanism for carding machines, an oscillatoryshaft, a comb blade attached to said shaft and arranged in spacedrelation thereto, driving means at both ends of said shaft, two armsextending transversely from said shaft, said arms carrying the combblade at substantially the node points of the fundamental resonance ofthe comb blade, spacer means arranged between the comb blade and theoscillatory shaft, and means cooperating with said space means forkeeping the comb blade, throughout its length, at a fixed distance fromthe oscillatory shaft; wherein said spacer means are sleeves, and themeans cooperating therewith for keeping the comb blade at a fixeddistance are wires strung from the oscillatory shaft to the comb blade,said Wires having a vibration dampening covering thereon and extendingsubstantially the full length thereof.

17. In a doffer comb mechanism for carding machines, an oscillatoryshaft, a comb blade attached to said shaft and arranged in spacedrelation thereto, driving means at both ends of said shaft, two armsextending transversely from said shaft, said arms carrying the combblade at substantially the node points of the fundamental resonance ofthe comb blade, spacer means arranged between the comb blade and theoscillatory shaft, and means cooperating with said spacer means forkeeping the comb blade, throughout its length, at a fixed distance fromthe oscillatory shaft; wherein said spacer means are sleeves, and themeans cooperating therewith for keeping the comb blade at a fixeddistance are wires strung from the oscillatory shaft to the comb blade,said wires being pivotally anchored to the oscillatory shaft at one endand fastened to the comb blade at the other end and carrying said spacersleeves, and there also being included means for tensioning the wiresand holding the spacer sleeves in compression.

18. In a doffer comb mechanism for carding machines, an oscillatoryshaft, a comb blade attached to said shaft and arranged in spacedrelation thereto, driving means at both ends of said shaft, two armsextending transversely from said shaft, said arms carrying the combblade at substantially the node points of the fundamental resonance ofthe comb blade, spacer means arranged between the comb blade and theoscillatory shaft, and means cooperating with said spacer means forkeeping the comb blade, throughout its length, at a fixed distance fromthe oscillatory shaft; wherein said spacer means are sleeves, and themeans cooperating therewith for keeping the comb blade at a fixeddistance are wires strung from the oscillatory shaft to the comb blade,said wires being pivotally anchored to the oscillatory shaft at one endand fastened to the comb blade at the other end and carrying said spacersleeves, and there also being included means for tensioning the wiresand holding the spacer sleeves in compression, said wires having avibration dampening covering thereon and extending substantially thefull length thereof.

19. A doffer comb mechanism comprising a drive shaft, drive meanstherefor, a cam on each end of the drive shaft, a parallel comb shaft,parallel crank arms, one on each end of the comb shaft, a connecting rodconnecting each arm with one of said cams, two arms on the comb shaftdiametrically spaced from the crank arms, a comb blade mounted on thearms, said arms being spaced inwardly from the ends of the comb bladeone-fourth of the length of the blade, a series of hollow spacers atuniformly spaced points on the comb blade and pivotally held on the nearside of the comb shaft, wires from the comb blade running freely throughthe spacers and comb shaft, and means on the opposite side of the combshaft for anchoring the wires under tension.

20. A doffer comb mechanism comprising a drive shaft, drive meanstherefor, a cam on each end of the drive shaft, a parallel comb shaft,panallel crank arms, one on each end of the comb shaft, a connecting rodconnecting each arm with one of said cams, two spaced arms on the combshaft, diametrically spaced from the crank arms, a comb blade mounted onthe arms, a series of hollow spacers at uniformly spaced points on thecomb blade and pivotally held on the near side of the comb shaft, wiresfrom the comb blade running freely through the spacers and comb shaftand means on the opposite side of the comb shaft for anchoring the wiresunder tension.

21. A mechanism as defined in claim 20 in which the hollow spacers arepivot ally held for movement solely in a plane perpendicular to the axisof the comb shaft.

22. A mechanism as defined in claim 20 in which the means for anchoringthe wires comprises a hollow bolt holding the end of the wire andadjustably tensioned in the side of the comb shaft.

23. A mechanism as defined in claim 20 in which the wires have avibration dampening cover throughout their length.

24. A mechanism as defined in claim 20 in which the spacers are alignedto the comb shaft by winged brackets.

25. A mechanism as defined in claim 20 in which the comb shaft has aplurality of counterweights diametrically disposed to the arms of thecomb shaft.

References Cited UNITED STATES PATENTS 2,118,975 5/1938 Hunt 19-106FOREIGN PATENTS 744,786 2/ 1956 Great Britain.

891,667 10/1953 Germany.

8,396 1884 Great Britain.

MERVIN ST'EIN, Primary Examiner.

I. C. WADDEY, Assistant Examiner.

